How important is it to add exactly 1 volume? - phenol:chloroform (Feb/20/2009 )

I have been wondering how important is it to add exactly 1 volume of Phenol:Chloroform:Isoamyl alcohol when doing DNA extraction....for example, you have 800ul of your solution and you would add 1ml of Phenol:Chloroform (instead of 800ul), would it matter?

-Wolverena-

no, the exact volume added would not matter. It is more important to phenol/chloroform extract until the interface is clear... whereby nearly all the protein in the sample has been removed.

-perneseblue-

You need to have AT LEAST that much. More is fine, less is NOT

-sciencedork-

They just tell you to add 1 volume so you don't overfill your eppi tube....